A personal computer is typically coupled to peripherals that serve as computer-user interfaces. Such peripherals may include a keyboard, a mouse, and a monitor. Typically standard cables connecting each peripheral are around four feet long. Because of the characteristics of the connecting cables and their interfaces, the cables do not provide a reliable peripheral connection when they are much longer than twenty feet.
There are situations where it is desirable to separate the computer from the peripherals at distances much greater than allowed by typical standard peripheral cables. The apparatus to extend the distance between a computer and peripherals is called an extender or an extension system. One such system, PC-Extender Plus is available from Cybex Computer Products of Huntsville, Ala. The PC-Extender Plus allows a keyboard, monitor, and mouse to be placed up to 600 feet away from the computer. An extender typically has two electronic boxes and several cables between the computer and the peripherals. As the demand for extenders increases, the need for more efficient use of cables has developed.
In existing extenders, standard coaxial cables, shielded cables, and unshielded cables serve as communication channels. In addition, custom cables have been developed to provide an improved communication channel for some extender systems. The cables connecting the computer to the peripherals may be confined in a binder or may be separate cables for each of the desired connections. The apparatus or electronic boxes connected to the ends of each cable serve as interfaces between the computer and the cable at one end and the peripherals and the cable at the other end.
Existing systems typically require nine pairs of wires. Three are for the video signals having red, green, and blue signals. One pair of wires is required for horizontal sync and another pair of wires for vertical sync. One pair of wires is required for the mouse data, the mouse clock, the keyboard data, and the keyboard clock. Further existing systems do not have provisions for additional peripherals such as speakers, microphones, a modem, serial ports, parallel ports or new devices.
Accordingly, it is the object of this invention to provide for more efficient and improved use of existing cables and at the same time reduce cost. In addition the invention will serve as a means for providing functions not available on existing extension systems.